This is the fourth in a series of blogs, shared with permission, about weeds in the garden. Each blog will discuss a common and specific weed found in Maine, its history, uses, what story it tells about the soil it grows in, and how to get rid of it. The original blogs, along with other gardening related blogs, can be found here.

Canada thistle, or Cirsium arvense is not actually from Canada. It is a native of Europe and Asia, and in that area it is typically called creeping thistle. Other names include lettuce from hell thiste, prickly thistle, way thistle, small-flower thistle, cursed thistle, field thistle, hard thistle, green thistle and perennial thistle. It is a plant considered to have originated during the Mesozoic and Paleozoic eras, preferring areas with moderate sunlight and temperatures, plenty of carbon dioxide and a great deal of ground water. The plant spreads through strong, deep root structures as well as through seeds.

You may want to just keep this plant around if you aren’t afraid to
keep cutting it back. Although it is a weed, the Canada thistle’s roots
can delve up to 20 feet deep – and bring all the nutrients back up to
the surface. Additionally, this ground breaking work makes it easier for
less vigorous plants to survive in a space.

Birds love the seeds of the thistle, especially goldfinches;
and it is at least as good as alfalfa for livestock. As a bee lover
(and a food lover) the best reason to keep Canada thistle around is
because it is considered a fantastic pollinator. One 2016 British study
found it was considered the second best producer of nectar sugar.
However, you can also eat them. In Portugal for instance, thistles are still collected and sold in markets.
Thistles are considered to be higher in fiber, protein, phosphorus,
magnesium, calcium, copper, zinc and other nutrients than many other
commonly eaten vegetables.

What does it mean?

Thistle is typically an indication your soil needs more acid. Correct this problem with soil amendments like ferrous sulfate or aluminum sulfate. Another way to get rid of thistles with is to use root secretions from tall marigolds Tagetes minuta or dahlias can kill it.

The easiest way to get rid of them is to have too much heat or too little water. Alternately preventing any sunlight from reaching the space after seedlings emerge will kill off the plants as well. Even a small fragment of the root will spread to create new plants. Avoid trying to dig up the plant, and instead chop it down before the flowers turn into seeds. If you do this several times, you will drain the root reserves and the plants will die.

Want to learn more?

If you would like to learn more about weeds, why they grow, and what that means about your garden, consider the following texts:

This is the second in a series of blogs, about ancient soil amendments used in the garden. Each blog will discuss a common and specific type of soil amendment used in the garden, along with documentation for its use, as well as occasionally discussing why a particular soil amendment was chosen, or its relation to modern gardening practices. The original blogs, along with other gardening related blogs, can be found here.

Manure is talked about quite frequently in husbandry and gardening texts of the period. Manure is unique in that it is both a substance you add to the soil as well as a practice you regularly complete. In the modern mind, manure is is synonymous with animal waste. This is not true in medieval texts. Sometimes manure means animal waste, other times it means anything biodegradable.

Medieval authors compare the dung of different animals as well. Cato outlines specifically that you can just spread pigeon dung on your fields, but you should store piles of other animal waste. Geoponika also discusses the benefits that come from different animal wastes. Walter of Henley warns his readers that manure alone will only benefit your soil for two or three years.

Although the practice is documented as post-medieval, the use of manure to heat winter cold frames is one that could easily have been used. There was a Victorian practice where a brick or stone box was combined with fresh, hot manure, giving several weeks of early heat to plants. Eve Otmar of The Colonial Williamsburg Foundation told me you would get about 4-6 weeks extra heat using this method.

This is the third in a series of blogs, shared with permission, about weeds in the garden. Each blog will discuss a common and specific weed found in Maine, its history, uses, what story it tells about the soil it grows in, and how to get rid of it. The original blogs, along with other gardening related blogs, can be found here.

Crabgrass is actually a short form for a number of types of the same species of plant. In this article I talk about large crabgrass or Digitaria sanguinalius which is a remarkable plant with the ability to smother other weeds and
act as its own mulch. A variety of other common names for it exist, including Polish Millet, hairy crabgrass, hairy finger-grass, crab finger grass, and purple crabgrass. About 10% of people are allergic to it, but if you aren’t among that 10%, rethink your hate of crabgrass.

Crabgrass, like many weeds I’ve been learning about, was brought to
the United States. The grass is highly nutritious and is used by farmers
for graze for animals. The seed is edible, and the plant is considered
to produce a high amount of grain. Each plant can produce about 150,000
seeds each!
The seed can be used as a flour, grain or fermented for use in beer. It
is also very fast growing – producing edible seeds in just eight weeks. Eastern Europeans used it as a grain, called kasha, and cultivated it in sandy soils in Poland.
We basically decided that corn sold better, and thus stopped cultivating
it here in the U.S!

What does it mean?

Crabgrass indicates very low levels of calcium and phosphorus, low
pH, low humus, very high chlorine levels and high levels of magnesium
and potassium. Basically, you have poor soil. You will need to really
work to fix the soil health to fully eliminate it, but it is a grain –
so if you don’t also stop future spread, it could simply become
healthier as you improve the soil.

It is difficult to kill because it prefers bad soil and drought.
Also, it easily regenerates and is fairly tolerant to chemicals. The best way to get rid of it is to keep your lawn at least 2-3 inches tall and
properly moist. Fertilize regularly and choose grasses suitable for your
climate. You could also apply corn gluten meal to your lawn 2-3 weeks before the seeds begin to germinate, but this
can inhibit all grass seed germination. One last option: remove large
sections of turf around the crab grass and kill off any remaining weed
seeds in that area before reseeding.

Want to learn more?

If you would like to learn more about weeds, why they grow, and what that means about your garden, consider the following texts:

This is the first in a series of blogs, about ancient soil amendments used in the garden. Each blog will discuss a common and specific type of soil amendment used in the garden, along with documentation for its use, as well as occasionally discussing why a particular soil amendment was chosen, or its relation to modern gardening practices. The original blogs, along with other gardening related blogs, can be found here.

After several years of gardening in a space, you will notice a steady decrease in how well the garden produces. For the modern gardener this is annoying, but very few of us in the western world live or die based on the production of our garden. During the Middle Ages, without grocery stores and mega-farms, this was a serious issue.

it is generally accepted that you have to add something to the soil to improve soil productivity. Typically this is done either by straight up adding something to the soil (a soil amendment) or by completing a process (a soil improving practice). Both have an important role. If a soil doesn’t have a characteristic or a mineral, it may be faster and more efficient to simply add what is missing. If the soil is merely low or constantly being drained of a mineral it might make more more sense to regularly perform a task, or build in a system, to replenish the soil.

The modern gardener, even the modern farmer, deals with soil decline quite simply – we order soil amendments from our farm supply or hardware store. If our soil lacks nitrogen, we buy a fluid or pellet mix to spread out and and water in. Obviously, our agrarian ancestors could not do this. Before I discuss the ways pre – industrial societies dealt with decreases in soil productivity, it will help to understand how it happens.

One aspect of soil health (which determines productivity) is fertility. According to the Queensland Government, soil fertility decline occurs when nutrients being removed from the soil in harvested products exceed nutrients being added to the soil. These nutrients can be removed in three ways – by growing crops, soil erosion, and leaching. These first two methods – growing crops and soil erosion cause most of the problems.

Growing crops both draws out and adds in nutrients to soil. Some plants (like peas) add soil nutrients like nitrogen to the soil if most of the plant is allowed to grow, die and compost in the space. Others, (like corn), need large amounts of soil nutrients in order to create healthy foods which is difficult to get back. The nutrients are generally pulled out of the soil into plants through their root structures. For example – lead in soil can be removed through growing (and than disposing) sunflowers through a process called phytoremdiation. If you plant too much of one type of plant – or don’t use proper balance, you hurt the soil health.

Erosion is when wind or water is able to remove nutrients, organic matter, clay or the soil itself from a piece of land. It “decreases nutrient bio-availability, root growth, plant fertility, biological productivity, moisture retention, and water filtration of soil, and erosion perpetuates further erosion” (Palmer, 2009). Although we commonly associate this problem with the “Dust Bowl” of American history, erosion happens every day. Stan Buman says soil can – in best case scenarios – only rebuild at a rate of .24 tons per acre. The same report found that the average soil loss in modern farming practices is 5.8 tons per acre. In a best case scenario, with no-tilling, you will still loose about .22 tons per acre, or just slightly less than you can rebuild. These numbers are designed for big farms but the point is clear – with any tilling or turning over at all, you wil loose soil – and also lose nutrients.

Over the following months, I will share some discussions about each of the different soil amendments and soil improvement practices I have found reference to in medieval or pre-medieval texts. Some of these may seem familiar to you as techniques we use in permaculture or modern organic farming, others may be new. Enjoy the reflection on the past – and I hope you generate some ideas on what you can try in your own gardens!

This is the second in a series of blogs, shared with permission, about weeds in the garden. Each blog will discuss a common and specific weed found in Maine, its history, uses, what story it tells about the soil it grows in, and how to get rid of it. The original blogs, along with other gardening related blogs, can be found here.

Queen Anne’s Lace, daucus carota, is the ancestor of
cultivated carrots. Tall and airy in appearance, it’s beautiful flowers
are a haven for pollinators on the sides of roads or abandoned city plots. It can be distinguished from poison hemlock through its hairy stems and distinct,
closely-bunched, flat-topped flower head. I was always told it was
poisonous (not unlike Henry Holly), but have since learned that isn’t accurate.

It is generally edible. The seeds are good in soups and stews, the flower head can be battered and fried.
The root is good grated, and tastes like carrots, but can become woody
(like any plant in the family that has gone to seed). It contains
vitamins A, B and C, biotin and also pectin.

Pliny and Dioscorides thought it had aphrodisiac properties, which may be because carrot leaves contain porphyrins which lead to the release of increased sex hormones. Chinese medicine
also considers the plant useful for use as a treatment for parasites,
diuretic and a bactericidal. Its thick sap has been used for cough and
congestion.

Despite all of these positive qualities – there is a significant
reason why women should be careful when consuming it. The plant, since Hippocrates,
was prescribed as a contraceptive and abortifacient. Scribonius used it
in a concoction for sterility. Pliny discusses the use of seeds for
this purpose. Much later, Culpeper does as well, also preferring the
seeds to the roots. Even today,
some women use the seeds as a contraceptive – chewing the seeds daily
during the period prior to ovulation and for a week after ovulation.
There is a theory, based on Chinese research, that the seeds block progesterone synthesis.

What does it mean?

Soil where Queen Anne’s Lace thrives is typically along roadsides,
pastures, building lots or really anyplace humans have disturbed the
soil. McCaman suggests it’s deep taproots indicate deep soil that could
be used for growing things.

The soil typically has very low amounts of phosphate, low amounts of
calcium and potash, and high amounts of iron, boron, chlorine and
selenium. All four of these should only be trace minerals. Pfeiffer
suggests the soil itself may have good drainage and a good ability to
break down dead plants in it, but may lack adequate moisture, decaying
plant matter or bacteria. McCaman agrees, there is a positive
correlation between the number of plants in an area and its soil
fertility.

To stop it’s growth and spread, apply well-rotted humus over manure
in areas when you fertilize. The plant primarily spreads through seeds,
so another good way to halt it’s growth is by cutting off the plant
close to the ground after it start to go to seed. Do not cut it before
the flowers start to die though, or like any carrot, it will spread from
the root instead.

Want to learn more?

If you would like to learn more about weeds, why they grow, and what that means about your garden, consider the following texts: